Gloucestershire 454 for 3 (Bracey 224*, O Price 77, Dent 65) beat Somerset 256 (Umeed 55, van Meekeren 3-34, Shaw 3-42) by 198 runs
Bracey crashed 30 fours and five sixes as the wicketkeeper-batter took centre stage, just four days after Somerset’s attack had seen India star Prithvi Shaw hit a double century against them for Northamptonshire.
Bracey’s innings easily saw him surpass the previous best List A score by a Gloucestershire batter, a mark that Tony Wright had set with 177 against Scotland at Bristol in 1977.
Gloucestershire’s total was also the second-highest ever in List A county cricket and beat the club’s previous record mark of 401 for 7 against Buckinghamshire in 2003.
The stage for the destructive batting, which saw the hosts hit a total of 15 sixes, was set by a 105-run opening stand between Bracey and Chris Dent in just 13.1 overs.
Dent smacked 65 from 38 balls before he was caught of Somerset teen George Thomas, but new man Oliver Price simply picked up the baton.
Price and Bracey shared an effortless 213-run second-wicket stand the pair dominating the away attack and setting up a final 10-over blitz that saw Gloucestershire add 136.
Price played the anchor role as Bracey took the Somerset attack apart before he fell to 19-year-old offspinner Shoaib Bashir for 77 from 83 balls in the 42nd over.
Gloucestershire only accelerated from there as Ireland international Harry Tector blasted 37 from 17 balls and Graeme van Buuren added an unbeaten 35 from 12 balls as Bracey remained to post the first double century of his Gloucestershire career in any format.
Umeed hit 55 from 46 balls before he was bowled by Van Meekeren while Tom Price followed his brother’s antics with the bat by removing Thomas and Rew.
When Van Meekeren bowled Somerset captain Sean Dickson for 24 the game slid out of the visitors’ control as they lost their final five wickets for 25 runs in 28 balls.
Shaw completed victory, which moves Gloucestershire up to third in Group B, when Bashir was caught by Tom Price. Somerset remain bottom of the group.